U need to adjust some values in the pathfinding.c ... first it didnt work for me too. Then i played around some hours with values ( the one u can adjust ). Then it worked perfect. Believe me, playing around with values will solve this. I dont have the values to my hand right now sry.

The main problem here is the c-trace tolerance distance between nodes. If its to high pathfinding trys to skip nodes. That why ur model trys to run through a block. Its too Long ago since i implemented it, i cant remember the exact problem. But now iam really happy with this script, thanx again to SuperKu ^^

@JustSid
Iam no rich man too, but if someone scripts a (perfect) working pathfinding system ready to use for 40 Euros, iam sure more than one person will buy it.